Vibratory tool



June 12, 1956 N. ANTON 2,749,676

VIBRATORY TOOL Filed Nov. 25, 1953 2 Sheets-Sheet l 74 e1 85 FIG. 5

| illllllllllmlllfllllllllm 76 .NVENTO i H: NICHOL 70 62 BY As ANTONATTORNEYS June 12, 1956 ANTON 2,749,676

VIBRATORY TOOL Filed Nov. 25, 1955 2 Sheets-Sheet 2 52 24 35 34 33 3 20f3 a 55 i V a F-' IG 9 y /3/@. Had,

INVENTOR. NICHOLAS ANTON I'IIIIIIIA ATTORNEYS VHBRATURY TQOL NicholasAnton, Park Ridge, ill.

Application November 25, 1953, Serial No. 394,334

ltl Claims. (Cl. 51-170) This invention relates to vibratory tools andmore particularly to vibratory tools of the type particularly welladapted for hand sanding and hand polishing op erations.

Vibratory sanders and polishers have heretofore been known in the art.However, such vibratory sanders and polishers which have been heretoforeknown have had several inherent disadvantages such as, for example:being heavy in weight; being weak in action; being relativelycomplicated in construction and operation; operating with undesirablevibration; or operating With an undesirable oscillating motion which,especially in sanding operations, did not produce desirable results. Itis the primary object of my invention to overcome the aforementioneddisadvantages.

It is the principal object of my invention to provide a vibratory toolof the aforementioned type embodying a sanding or polishing block whichis supported in the tool in a novel and expeditious manner and which,during the operation of the tool may be operativel-y reciprocated by analternating electromagnet in a novel and expeditious manner.

A further object is to afford a novel vibratory tool of theaforementioned type wherein the sanding or polishing block reciprocatesthrough a relatively long path of travel in substantially a single planewith a minimum of vibration or oscillation transversely to such plane.

Another object of the invention is to afford a novel vibratory tool ofthe aforementioned type wherein the throw or movement of the blockthereof may be quickly and easily adjusted in a novel and expeditiousmanner.

Yet another object of my invention is to afford a vibratory tool of theaforementioned type which may be readily manually supported and handledby the operator.

A further object of my invention is to afford a vibratory tool of theaforementioned type which is sturdy in construction, efficient inoperation, and which may be economically produced commercially.

Another object is to afford a vibratory tool of the aforementioned typewherein sand paper, a polishing cloth, or the like may be supported on areciprocal block in a novel and expeditious manner.

A further object is to afford a novel tool of the aforementioned typeembodying novel retaining or clamping structure on the reciprocal blockthereof.

A further object is to afford a novel tool of the afore-' mentioned typeembodying novel retaining or clamping devices for sand paper, polishingcloths, or the like which can be quickly and easily operated and whichare positive in retaining operation.

Another object is to construct a vibratory tool of the aforementionedtype which embodies novel retaining or clamping structure which isreadily actuated and which during actuation is efiective to tension,sand paper, a polishing cloth, or the like, on the block in a novel andexpeditious manner.

2,749,576 Patented June 12, 11956 Other and further objects of thepresent invention will be apparent from the following description andclaims and are illustrated in the accompanying drawings which, by way ofillustration, show a preferred embodiment of the present invention andthe principles thereof and what I now consider to be the best mode inwhich I have contemplated applying these principles. Other embodimentsof the invention embodying the same or equivalent principles may be usedand structural changes may be made as desired by those skilled in theart without departing from the present invention.

In the drawings:

Fig. l is a side elevational view of a vibratory tool embodying theprinciples of my invention;

Fig. 2 is a top plan view of the vibratory tool shown in Fig. I;

Fig. 3 is a view somewhat similar to Fig. l but with the near half ofthe casing removed and with certain of the parts shown in Fig. 1 beingshown in section;

Fig. 3A is a detail sectional view taken substantially along the line3A-3A in Fig. 3;

Fig. 4 is a sectional view taken substantially along the line 4-4 inFig. 3;

Fig. 5 is an elevational view of the half of the casing shown in Fig. 3;

Fig. 6 is a detail elevational view of a portion of the tool shown inFig. 3;

Fig. 7 is a detail sectional view taken substantially along the line 7-7in Fig. 6;

Fig. 8 is a sectional view taken substantially along the line 8-8 inFig. 3;

Fig. 9 is a sectional view taken substantially along the line 99 in Fig.8;

Fig. 10 is a detail sectional view somewhat similar to Fig. 9 with partsthereof disposed in different operating positions;

Fig. 11 is a detail sectional View of the portion of the mechanism shownin Fig. 10 with parts thereof disposed in different operating positions;

Fig. 12 is a detail sectional view similar to Fig. 11 with parts thereofdisposed in different operating positions;

Fig. 13 is a detail sectional view similar to Figs. 11 and 12 with partsthereof shown in different operating positions;

Fig. 14 is a perspective view of a portion of the mechanism shown inFigs. 8 to 13, inclusive;

Fig. 15 is a perspective view of the mechanism shown in Fig. 14, withthe parts thereof disposed in diiferent operating positions.

To illustrate the principles of my invention, a vibratory sander orpolishing tool 20, comprising a preferred embodiment of my invention, isshown in the drawings. The vibratory tool 2% comprises, in general, acasing 22 enclosing an alternating electro-magnet 24, which is operableto reciprocate a shoe or block 26 disposed outwardly of the casing 22and mounted on two supporting members 28 and 29 which extend downwardlyfrom the electro-magnet and project outwardly through the open bottom31, Figs. 3 and 4, of the casing 22.

The electro-magnet 24 comprises, in general, a core 33, a winding 34,and an armature 35. The core 33 is preferably of the E-type and formedof a plurality of laminations 37, Fig. 4, covered by a housing 38,having two side walls 44) and 41, and three end walls 43, 44 and 45,Figs. 3 and 4. Each of the side walls 40 and 41 have an ear 4% and 41a,respectively, Figs. 3 and 3A, formed as an integral part thereof andprojecting rearwardly from the laminations 37 for a purpose which willbe discussed in greater detail presently.

The armature 35 like the core 33 is preferably composed of a pluralityof laminations 47, Fig. 3A, on which Q is mounted a housing 49. Thehousing 49, Figs. 3 and 3A, includes two side walls 51 and 52 and an endwall 53. A bearing 34 is mounted on and extends through the upper endportion of the armature 35, and the armature 35 is pivotally mounted onthe core 33 by means of a pin or bolt 55, which extends through thebearing 34 and the ears 40a and 41a of the housing 38 and through oneend of the armature 35, which is disposed between the ears 40a and 41a,Fig. 3A. The sleeve 34 is mounted in the armature 35 with a bearing fitand the armature 35 rotates thereon between the cars 40:: and 41a.

The winding 34 is of a conventional type and is preferably mounted onthe center bar 33a of the core 33, Figs. 3 and 4, and is connectedthrough a switch 57 to lead wires 59 and 60.

The block 26, which is reciprocated by the electromagnet 24 during theoperation of my novel vibratory tool 20, as will be discussed in greaterdetail hereinafter, includes a plate 62, having an upper face 63 and alower face 64, and a pad 66 mounted on the lower face 64. The plate 62may be made of any suitable material, such as, for example, aluminum andthe ends and sides thereof are preferably turned down to form end wallsor end flanges 68 and 69 and side walls or side flanges 70 and 71respectively, Figs. 3 and 4. Ribs 74 are preferably formed in thecentral portion of the plate 62 to thereby stiffen and strengthen thesame. The pad 66 may be formed of any suitable material such as felt,rubber, or the like, and is preferably adhesively secured to the lowerface 64 and the plate 62 between the flanges 68--71.

In the operation of my novel vibratory tool 20 as will be presentlydescribed in greater detail, a sheet of sand paper, or polishingcloth,'or the like, is normally mounted on the lower face of the pad 66,and is'firmly held thereon by clamping units 75 and 7 6, Figs. 3 and 10,mounted on the upper face of the plate 62, the clamping units 75 and 76forming a readily actuated and positively acting device for thispurpose, as will be discussed in greater detail hereinafter.

The block 26 is then caused by the armature 24 to rapidly reciprocate ina forward and rearward direction, or, that is, to the right and theleft, respectively, as viewed in Fig. l, to thereby impart a series ofrapid reciprocating polishingor sanding strokes to the block 26.

The supporting member 28 includes a leaf spring 78 and the armature 35,Fig. 3, the lower end of the leaf spring 78 being secured to the plate62 by suitable means such as rivets 79, and the upper end of the leafspring 68 being secured to the end wall 53 of the housing 52 on thearmature 35 by suitable means such as rivets 81.

The supporting member 29 comprises a double-leaf spring 82; the spring82 comprises two spring leaves 82a and 32b which are disposed insubstantially upright position, Fig. 3. The leaf 82b is considerablyshorter in length than the leaf 82a, Fig. 3, and is mounted on the upperend portion of the latter, being secured thereto by suitable means suchas rivets 87.

The lower end portion of the spring 82 is connected to the plate 62 ofthe block 26 by suitable means such as rivets 35, Fig. 3, and the upperend portion thereof is mounted on the end wall 45 of the core housing 38of the transformer 24 by the two clamps 91 and 91a, Figs. 3, 6 and 7,which are identical in construction. The spring 82 is adjustably mountedon the end wall 45 of the armature 24 by the clamps 91 and 91a, as willbe discussed in greater detail presently.

Each of the clamps 91 and 91a includes a rear backing plate 93, Fig. '7,and a front plate 94, and is mounted on the upper end portion of theleaf spring 82 with the latter disposed between the plates 93 and 94. Aslot 96 is formed in the upper end portion of the two leaves 82a and 82bof the spring 32, Figs. 6 and 7, and a similar 4 slot 97 is formed inthe upper end portion of the end wall 45 of the housing 38. The leafspring 82 when disposed in operative position, is mounted on the endWall 45 in such position that the slots 96 and 97 are disposed inalignment with each other.

Each of the clamps 91 and 91a includes a bolt 99 which, as best seen inFigs. 3, 6 and 7, extends through the slot 97 in the end wall 45, thebacking plate 93, the slot 96 formed in the leaf spring 82, and theplate 94. A nut 101 is mounted on the bolt 99 and may be adjustedthereon to effectively clamp the end wall 45, clamping plates 93 and 94,and the leaf spring 32 together to thereby secure the leaf spring 82 inoperative position on the end Wall 45 of the core 33. It will be seenthat with the slotted construction of the end wall 45 and the leafspring 82, the vertical position of the leaf spring 82 on the side wall45 may be readily adjusted by loosening the nuts 101, moving the leafspring 82 upwardly or downwardly into the desired position on the Wall45 and then tightening the nuts 101.

The casing 22 which I prefer to use on my novel vibratory tool 20 may bemade of any suitable material such as, for example, a phenolicthermo-setting resin and is preferably split along the longitudinalcenter line thereof to afford two halves 22a and 22b which may bereleasably secured together by suitable means such as three bolts 103,104 and 105, Figs. 1 and 2. Each of the halves 22a and 22b of the casing22 of my novel vibratory tool 20 shown in the drawings is identical inconstruction, being merely reverse or mirror images of each other toafford opposite sides for casing 22. Thus, it will be seen that, asshown in the half 22b of the casing 22 shown in Fig. 5, each of thehalves 22a and 22b of the casing 22 is substantially cup shaped, havinga top flange 107, a rear flange 100, and a front flange 109, each ofwhich flanges is disposed in abutting relation to a corresponding flangeon the other half of the casing when the two halves 22a and 22b aredisposed in the operative relation to each other shown in Figs. 1, 3 and4. Each of the halves 22a and 22b of the casing 22 embodies a pluralityof ventilating slots 112 formed in the side wall 113 thereof; asupporting ridge or shelf 115 formed on the lower inner face of the sidewall 113; a pair of abutment members 117 and 118 formed on the upper endportion of the inner face of the side wall 113 and projecting downwardlyfrom the top flange 107; a plurality of reinforcing or strengtheningribs 119 formed on the upper end portion of the inner face of the sidewall 113; a recess 121 formed in the rear flange 108 and extendingtherethrough; and an inwardly opening recess 123 formed in the frontflange 109, with another recess 124 of reduced cross section extendingoutwardly through the remainder of front flange 109 from the recess 123.

The core 33 and the armature 35' of the electro-magnet 24 are of suchsize that they may be disposed in assembled relation to each other andplaced in one of the halves of the casing 22 such as, for example, thehalf 22b of the casing 22 as shown in Fig. 3, within the confines of theflanges 107, 103 and 109 thereof, and when so disposed the lower wall 44of the housing 33 of the core 33 rests on the shelf 115, and the endwall 43 of the housing 38 is disposed in abutting relation to theabutment members 117 and 118, and the side wall 49 of the housing 38rests against the reinforcing ribs 119 to thereby support the core 33 inspaced relation to the major portion of side wall 113 of the half 22b ofthe casing 22. Also, when the transformer 24 is so disposed in the half22b of the housing 22, the lead-in wires 59 and 60 may be mounted in therecess 121, and the switch 57 may be mounted in the recess 123, with thecontrol button 57:: thereof projecting outwardly through the recess 124.a

With the electro-magnet 24, switch 57, and the lead I wires 59 and 60disposed in this manner in the half 22b be mounted on the half 22b inoperative position as shown in Figs. 1, 2 and 4, whereby it is similarlyengaged with the transformer 24, the wires 59 and 6t) and the switch 57.The bolts 163, 194 and 1615 may then be inserted through the halves 22aand 22b of the casing 22, and the nuts 163a, 164a and 1(l5a thereon,respectively, may be tightened to thereby firmly clamp the halves 22aand 22b of the casing 22 together. With this construction it will beseen that the novel vibratory tool 20 shown in the accompanying drawingsmay be readily constructed and quickly and easily assembled, and whenassembled the electro-magnet 24 and the other parts are firmly securedin operative position in a novel and a practical manner.

As is best seen in Fig. 3, the supporting members 28 and 29 are securedto the electro-magnet 24 and the block 26 in such a manner that theblock 26 is supported by the electro-magnet 24, and the electro-magnet24, the block 26, and the supporting members 28 and 29 form a unitarystructure which may be readily inserted into or removed from the casing22 as a unit.

It will be noted that the armature 35 is pivotally mounted at its upperend to the extensions 4% and 41a of the core housing 33 of thetransformer 24 by a fixed pivot 55. Also, it will be seen that the lowerend portion of the leaf spring 78 is formed into a rearwardly openingsubstantially arcuate-shaped bend 126, and the lower end portion of theleaf 82a of the spring 82 is likewise formed into a rearwardly openingsubstantially arcuateshaped bend 127. Immediately above the bend 127,the leaf 52a of the spring 52 is formed into a forwardly openingsubstantially arcuate-shaped bend 123 that terminates at its upperlimits in downwardly spaced relation to the leaf 82b, Fig. 3. Accordingto my theory of the operation of my device these structural features andthe combining thereof in the novel and expeditious manner embodied in myinvention play an important part in the realization of the improvementsafforded by my novel vibratory tool. 1 have found that with my novelvibratory tool 26 constructed substantially in accordance with thedisclosure made herein, the block 26 during operation of the tool 20reciprocates along a path of travel closely simulating a straight planeand with a minimum of objectionable vertical or lateral transversemovement.

The armature 35, when disposed in oil position, is normally disposed atthe position shown in Fig. 3 wherein it is disposed in a downwardlyopening rearwardly extending angle to the core 33. During operation ofmy novel vibratory tool 23 the armature 35 is alternately pivoted aboutthe fixed pivot .55 in a counterclockwise direction as viewed in Fig. 3from the position shown in Fig. 3 toward the core 33, and in a clockwisedirection from a position closely adjacent the core 33 back toward theposition shown in Fig. 3. Such movement of the armature 35 is effective,through its connection by the spring 78 to the block 26, toalternatively move the block 26 forwardly and rearwardiy or, that is,the right and left as viewed in Fig. 3.

The springs 78 and 52 are efiective to prevent the armature 35 fromstriking the core 33 of the transformer 24 during oscillation of thearmature 35 in the operation of the tool 2-0. Adjustment of the throw ofthe armature 35 and of the throw of the block 26 may be readily effectedby adjusting the spring 82 in the brackets 91 and 91a to thereby adjustthe effective len th of the spring 82. This may be normally accomplishedby adjusting the spring 8-2 into the position in the brackets 91 and 91awherein the unit is tuned to produce maximum throw of the block 2-6 andmaximum power, and then moving the bracket 31a to a position wherein,with the tool turned oft, the force necessary to manually hold the blockin forwardly displaced position equivalent to the aforementioned maximumthrow of the block is between fifteen and twenty per cent less than wasnecessary to so hold the block when the spring 82 was disposed in thetuned position. With the vibratory tool 20 adjusted in this manner it isassured that in normal operation, the armature 35 will not strike thecore 33, and that with the halves 20a and 22b of the housing 22 tightlyclamped in operative position over the transformer 24, the throw of theblock 26 will remain in its most efiective range for efficientoperation.

As was previously mentioned, the shoe or block 26 embodies as a partthereof novel clamping units 75 and 76 which are effective to securelyand positively hold wiping sheets such as sand paper, polishing cloths,or the like, in operative position on the lower face of the pad 66 andare, in addition, effective to automatically tension the sand paper orcloth on the pad 66 during the actuation of the clamping devices intoclamping position.

As is best seen in Figs. 8 to 15, the clamping units 75 and 76 eachembody a clamping plate 131 and a leaf spring 13.3. The leaf spring 133is substantially of a modified W-shape, Figs. ll, 12 and 13, embody along outer leg 135, a short outer leg 1.36, and two intermediate legs137 and 138. The short leg 136 has a free end portion 14%, and isconnected at its opposite end to the end of the leg 13% to form ajunction 142 therewith, and the end of the leg 1.38 opposite thejunction 14-2 is connected to the leg 137 to form a junction 143 withthe latte The leg 135, like the leg 136, has a free end portion 1' andthe end of the leg opposite the free end portion M4 is connected to theend of the leg 137 opposite the junction 143 to form a junction 145.

The clamping plate 131 may be formed of any suitable material, such as,aluminum, and includes an elongated leg 151, having one freelongitudinal edge 153. An elongated fiange is mounted on thelongitudinal edge of the leg 151 opposite the free edge 153 to form ajunction 154 therewith along substantially the full length of the leg151. The flange 155 forms an integral lateral extension of the leg 151which is disposed at an inwardly and upwardly opening obtuse angle tothe plane of the leg when the leg 151 is disposed in normal clampedposition, Figs. 10 and 13.

Two ears 157 and 158 project from the ends of the leg 151 in asubstantially perpendicular relation thereto and in substantiallyparallel relation to each other. Two ears 163 and 164 project fromopposite ends of the flange 155 in substantially longitudinal alignmenttherewith and afford handles for actuating the clamping units 75 and inas will be discussed presently.

An elongated slot 161 is formed in the longitudinal central portion ofthe leg 151 in a substantially parallel relation to the free edge 153thereof, and is disposed adjacent to the junction 154 with the flange155.

The inner end portion of the leaf spring 133, adjacent the free end 144of the leg 135 is secured in juxtaposition to the upper face of theplate '62 of the block 26 by suitable means such as the rivets 79, Figs.3, 9 and 12. The other end portion of the leaf spring 133 extendsoutwardly through the slot 161 and is so disposed therein that when theclamping plate 131 is disposed in normal operating positions the leg 151thereof is disposed between the legs 137 and 133 of the spring 133, andthe junction 143 is disposed in engagement with, or closely adjacent tothe lower edge of the slot 161. In the operation of the clamping device75, and for a purpose which will be discussed in greater detailpresently, the clamping plate 131 may be rotated around the ears 157 and158 between a fully open position shown in Fig. 11, and a fully closedclamping position shown in Fig. 13, the plate 131, in moving betweenthese two positions passing through an intermediate of temporary holdingposition shown in Fig. 12.

In the fully open position, shown in Fig. 11, the clamping plate 131 issupported on the ears 157 and 158 which rest on the top face 63 of theplate 62, and the leg 15.1 is disposed in rearwardly projecting,upwardly spaced, substantially parallel relation to the plate 62. Inthis position, the free edge of the flange 155, opposite the 7 junction154 rests on the upper face 63 of the plate 62, and the leg 133 of thespring 133 is disposed in downwardly urging engagement with the leg 151of the plate 131 adjacent to the free edge 153 thereof. To retain theclamping plate 131 in this position, the operator may manually applydownward pressure on the flange 155 or the ears 163 and 164 thereof.

In the intermediate or temporary holding position, Fig. 12, the clampingplate 131 is disposed in such position that both the free edge 153 ofthe leg 151 and an edge portion of the ears 157 and 158 are disposed inengagement with the upper face 63 of the plate 62 with the leg 151 ofthe clamping plate 131 projecting outwardly or rearwardly from theflange 155 and being disposed at a forwardly opening acute angle to theplate 62. With the plate 131 disposed in this position, the leg 138 ofthe spring 133 is disposed in juxtaposition to the outwardly disposedface of the leg 151 and the junction 143 is disposed in engagement withthe lower edge of the slot 161, whereby the spring 133 is effective tourge the clamping plate 131 to pivot in a counterclockwise directionaround the ears 157 and 158 and thereby urge the free edge 153 of theleg downwardly toward engagement with the plate 62.

In the fully closed or clamping position shown in Fig. 13, the clampingplate 131 is disposed in such position that only the free edge 135thereof is engaged with the plate 62, the flange 155 and the ears 157and 158 projecting upwardly from th leg 151, and the leg 151 beingdisposed in a rearwardly or outwardly opening acute angle to the plate62. When the plate 131 is disposed in this position the spring 133 isengaged with the plate 131 at three places of contact and is effectiveto firmly but yieldingly latch the plate 131 in this position. Thus, itwill be seen that the junction 145 is disposed in engagement with theinwardly disposed face of the leg 151, the leg 138 rests on the loweredge of the slot 161, and the free edge portion 141) of the leg 136 isdisposed in engagement with the rearwardly or outwardly disposed face ofthe flange 155.

It will be seen that when the plate 131 is disposed in this position theleg 151 has moved inwardly past the center of rotation of the plate sothat the spring is effective to firmly hold the plate 131 in thisposition and, in effect, urges the plate 131 substantially along theplane of the leg 151 into clamping engagement with the face 63 of theplate 62. To move the plate 131 from the clamping position shown in Fig.13 to the intermediate position shown in Fig. 12 the operator may exertforwardly or inwardly directed manual pressure on the flange 155 or theears 163 or 164 thereof to rotate the plate 131 in a clockwisedirection, as viewed in Fig. 13, against the latching action of thespring 131.

' The clamping unit 76 is of identically the same construction as theclamping unit 75 and, in fact, the parts of the clamping units 75 and 76are interchangeable. Therefore, the parts of the clamping unit 76 areidentified in the drawings by the same reference numerals as the partsof the clamping unit '75 but With the suffix a added thereto.

In the operation of my novel vibratory tool, when it is desired to placea wiping sheet such as a sheet of sand paper or a polishing cloth inoperable position on the lower face of the block 26, this may be quicklyand easily accomplished. First, the clamping plate 131 of the clampingunit 75 may be manually moved by the operator into the fully openposition shown in Fig. 11 and the one end portion of the wiping sheet Smay be inserted inwardly under the leg 151 in a forward direction andparallel to the upper face 63 of the plate 62 until that end of thesheet S is disposed in abutting relation to the ears 157 and 158. Theoperator may then release the clamping plate 131 of the clamping unit 75and permit the same to be rotated by the spring 133 into the temporaryholding position shown in Fig. 12 wherein the free edge 153 of the leg151 is firmly held in position to clamp the rear end portion of thesheet S against the plate 62. The sheet S may then be extended acrossthe lower face of the block 26 and, with the clamping pate 131a of theclamping unit 76 held in fully opened position by the operator, thefront end portion of the sheet S may be similarly fed into a positionwherein it is disposed in engagement with the ears 156a and 158a of theclamping unit 76. The operator may then permit the clamp plate 131a tobe rotated into its temporary holding position by the spring 133a tothereby firmly clamp the front end portion of the sheet S against theupper face 63 of the plate 62.

Normally, when the sheet S is being held by the units and 76, with thelatter disposed in their temporary holding positions, the sheet S is nottightly tensioned across the lower face of the block 26, but is somewhatloose as illustrated in Fig. 9. This is normally true because it issomewhat diflicult to pull the sheet S tight with one hand whileoperating a clamping or holding device with the other hand. This is oneof the difficulties encountered with many of the clamping devicesheretofore known in the art because with such earlier devices it wasdiflicult to ever get a sheet of sand paper or a polishing clothsufficiently tight on a supporting member to afford the desired wipingsurface. However, it is immaterial in the operation of my device thatwhen the sheet S is disposed in this temporary holding position it maybe somewhat slack on the block 26 because in moving the clamping units75 and 76 from the temporary holding positions thereof into theaforementioned fully close clamping position thereof, the clamping units75 and 76 are effective to automatically tension the wiping sheet S onthe block 26. To do this, the operator merely needs to rotate bothclamping units 75 and 76 from their temporary holding positions intotheir fully closed or clamping positions. During such movements of theclamping plates 131 and 131a, the free edges 153 and 153a, respectively,thereof are moved inwardly from the outer ends of the block 26 and,during such movement are firmly held by the spring 133 in engagementwith the respective rear and front ends of the sheet S and thus areeffective to move these rear and front end portions of the sheet Sinwardly toward each other along the upper face 63 of the plate 62,thereby taking up the slack in the sheet S and tensioning the sheet S onthe block 26.

It will be seen that in releasing a sheet S from clamped position on theblock 26, first one of the clamping units 75 or 76, and then the other,need merely be moved by the operator from fully closed position intofully opened position and the corresponding end of the sheet S manuallyremoved from beneath the clamping plate 131.

From the foregoing it will be seen that I have afforded a novelvibratory tool of novel construction and of improved operation.

Also it will be seen that I have afforded a novel vibratory tool whereina polishing or sanding member is supported and actuated in a novel andexpeditious manner.

In addition it will be seen that I have afforded a novel vibratory toolwherein such polishing members or sanding members may be quickly andeasily mounted in, and removed from, operative position therein and areheld in such position by novel clamping units.

Thus, while I have illustrated and described the preferred embodimentsof my invention, it is to be understood that these are capable ofvariation and modification.

I claim:

1. A vibratory tool comprising elongated plate means, an alternatingelectro-magnet including a core, and an armature pivotally mounted onsaid core for swinging movement toward and away from said core uponoperation of said electro-rnagnet, and spring means supporting saidplate means from said electro-magnet for movement by said armature uponsaid operation of said electromagnet, said spring means comprising twoelongated leaf springs disposed transversely to the length of said platemeans, each of said leaf springs having one end portion mounted on saidplate means, one of said leaf springs having its other end portionmounted on said armature for movement therewith, and the other of saidleaf springs having its other end portion mounted on said core, saidother leaf spring having a double arcuate bend between said plate meansand said core.

2. A vibratory tool comprising elongated plate means, an alternatingelectro-magnet including a core, and an armature pivotally mounted onsaid core for swinging movement toward and away from said core uponoperation of said electro-magnet, and spring means supporting said platemeans from said core for movement by said armature upon said operationof said electro-magnet, said spring means comprising two elongated leafsprings, one of said leaf springs having one end portion mounted on saidarmature, and having another end portion mounted on said plate means insupporting relation thereto, the other of said leaf springs having oneend portion mounted on said core, and having another end portion mountedon said plate means in supporting relation thereto, each of said leafsprings having a substantially arcuate-shaped bend therein between saidend portions of the respective spring, said bends opening in the samegeneral direction, and one of said springs having a second substantiallyarcuate-shaped bend between said end portions thereof, said second bendopening in the opposite general direction from the first mentioned bendin said last mentioned spring.

3. An electrically operated sander comprising an alternatingelectro-magnet including a core, an armature exposed to the field ofsaid electro-magnet, said armature being pivotally mounted on a fixedpivot on said core for rotation around said pivot toward and away fromsaid core upon operation of said electro-magnet, a sanding block, andmeans for mounting said sanding block on said armature and said core formovement by said armature upon said rotation of the latter, said meanscomprising two leaf springs, one of said leaf springs being mounted onsaid block and said armature, and the other of said leaf springs beingmounted on said block and said core.

4. An electrically operated sander comprising an alternatingelectro-magnet including a core, an armature exposed to the field ofsaid electro-magnet, said armature being pivotally mounted on a fixedpivot on said core for rotation around said pivot toward and away fromsaid core upon operation of said electro-magnet, a sanding block andmeans for mounting said sanding block on said armature and said core formovement by said armature upon said rotation of the latter, said meanscomprising two leaf springs, one of said leaf springs being mounted onsaid block and said armature, and the other of said leaf springs beingmounted on said block and said core, each of said leaf springs having asubstantially arcuate-shaped bend disposed between said block and saidelectro-magnet, said bends opening in the same general direction.

5. An electrically operated tool for sanding, polishing, or the like,and comprising an alternating electromagnet including a core, anarmature exposed to the field of said electro-magnet, said armaturebeing pivotally mounted on a fixed pivot on said core for rotationaround said pivot toward and away from said core upon operation of saidelectro-magnet, a shoe, and means for mounting said shoe on saidarmature and said core for movement by said armature upon said rotationof the latter, said means comprising two leaf springs, one of said leafsprings being mounted on said shoe and said armature, and the other ofsaid leaf springs being mounted on said shoe and said core, each of saidleaf springs having a substantially arcuate-shaped bend disposed betweensaid shoe and said electromagnet, said bends opening in the same generaldirection and each being formed transversely to the wide faces of therespective spring in which it is formed, and said other of said springshaving a second bend formed therein between said first mentioned bendtherein and said core, said second bend opening in the opposite generaldirection from said first mentioned bends.

6. An electrically operated sander comprising an alternatingelectro-magnet including a core, an armature exposed to the field ofsaid electro-magnet, said armature being pivotally mounted on a fixedpivot on said core for rotation around said pivot toward and away fromsaid core upon operation of said electromagnet, a sanding block, andmeans for mounting said sanding block on said armature and said core formovement by said armature upon said rotation of the latter, said meanscomprising two leaf springs, one of said leaf springs being mounted onsaid block and said armature, and the other of said leaf springs beingmounted on said block and said core, said other spring having a doublebend disposed between said block and said core with the bends thereofopening in opposite directions and each being transverse to the widefaces of said other spring.

7. A vibratory tool comprising a casing, alternating electromagneticmeans including a core mounted in said casing, an armature exposed tothe field of said electromagnetic means, said armature being pivotallymounted in said casing on a fixed pivot for rotation around said pivotupon operation of said electro-magnetic means, a supporting member, andmeans for mounting said supporting member for movement by said armaturerelative to said casing upon said rotation of said armature, said lastnamed means comprising two elongated leaf springs, one of said leafsprings being mounted on said supporting member and said armature, andthe other of said springs having one end portion mounted on saidsupporting member, and another end portion mounted in said casing infixed position relative to said electro-magnetic means.

8. A vibratory tool comprising alternating electromagnetic meansincluding a core, an armature exposed to the field of saidelectro-magnetic means, said armature being pivotally mounted by a fixedpivot on said core for rotation around said pivot toward and away fromsaid core upon operation of said electro-magnetic means, a casingenclosing said electro-magnetic means and said armature, said casingbeing disposed in clamping engagement with said core to thereby supportsaid core and said armature in operative position in said casing, anelongated supporting member disposed outwardly of said casing insubstantially parallel relation thereto in operative position to supporta wiping member, and means disposed in operative position between saidcasing and said supporting member for mounting said supporting member insaid operative position of said supporting member for reciprocation bysaid armature relative to said casing upon said rotation of saidarmature, said last named means comprising two elongated leaf springs,one of said leaf springs having one end mounted on said armature, andanother end mounted on said supporting member, the other of said leafsprings having one end portion mounted on said core, and another endportion mounted on said supporting member, said core, armature,supporting means, and mounting means, being movable as a unit into andout of said respective operative positions.

9. A vibratory tool comprising alternating electromagnetic meansincluding a core, an armature exposed to the field of saidelectro-magnetic means, fixed pivot means mounted on said core, saidarmature being pivotally mounted on said fixed pivot means for rotationthere around toward and away from said core during operation of saidelectro-magnetic means, an elongated casing enclosing saidelectro-magnetic means and said armature, said casing having twolongitudinally extending separable portions, said portions beingnormally disposed in clamping relation to said core for supporting saidcore and said armature, an elongated supporting member disposedoutwardly of said casing in substantially parallel relation thereto, andmeans for mounting said supporting member for longitudinal reciprocatorymovement by said armature upon said rotation of said armature, said lastnamed means comprising two leaf springs, 'one of said leaf springshaving one end portion mounted on said armature and another end portionmounted on said supporting member, the other of said leaf springs havingone end portion adjustably mounted on said core for longitudinalmovement therealong, and another end portion mounted on said supportingmember, each of said leaf springs having a substantially arcuate-shapedbend therein between said end portions thereof, said bends opening inthe same general direction, and said other leaf spring having anothersubstantially arcuate-shaped bend disposed between said first mentionedbend therein and said one end portion thereof, said other bend openingin substantially the opposite direction from said first mentioned bends.

10. A vibratory tool comprising alternating electromagnetic meansincluding a substantially E-shaped core, two ears projecting rearwardlyfrom said core in position to form two substantially parallellongitudinal extensions of one leg of said core, an elongated armatureexposed to the field of said electro-magnet, a fixed pivot mounted insaid ears and extending through one end portion of said armature, saidarmature being pivotally mounted on said pivot for rotation therearoundtoward and away from said core during operation of said electromagneticmeans, an elongated supporting member, means supporting said supportingmember from said armature and said core for longitudinal movement bysaid armature upon said rotation of said armature, said last named meanscomprising two leaf springs, one of said leaf springs having one endportion mounted on said armature, and another end portion mounted onsaid supporting member, and the other of said leaf springs having oneend portion mounted on said core, and another end portion mounted onsaid supporting member in spaced relation to said one leaf spring, eachof said leaf springs having a substantialiy arcuate-shaped bend, saidbends opening in the same general rearward direction, and said otherleaf spring having another substantially arcuate-shaped bend disposed onthe opposite side of said first-mentioned bend therein from saidsupporting member, said other bend opening in the general oppositedirection from said first mentioned bends, and a casing enclosing saidcore and said armature, said casing having inwardly projecting portionssupportingly engaging said core in spaced relation to said armature.

References Cited in the file of this patent UNITED STATES PATENTS2,280,446 Nyman Apr. 21, 1942 2,324,292 Dremel July 13, 1943 2,509,561Dremel May 30, 1950 2,546,087 Burleigh Mar. 20, 1951 2,585,637 DremelFeb. 12, 1952 2,634,559 Carmichael Apr. 14, 1953

